It looks like the behaviour changed (i.e. was fixed) between 5.6 and 5.8: 
    $ perl5.6.0 -Mutf8 -e 'print "b" =~ /[A-C]/i ? "true\n" : "false\n
+"'
    false

    $ perl5.8.0 -Mutf8 -e 'print "b" =~ /[A-C]/i ? "true\n" : "false\n
+"'
    true

[download]

--
John.

In reply to Re: Ranges in case insensitive regexps in unicode mode by jmcnamara
in thread Ranges in case insensitive regexps in unicode mode by IlyaM

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